Fitting construction for tanks



F. J. PEPERSACK 2,336,885

FITTING CONSTRUCTION FOR TANKS Filed July 18, 1942 2 Sheets-Sheet 1 Dec. 14, 1943. P P s c 2,336,335

FITTING CONSTRUCTION FOR TANKS Filed July 18, 1942 2 Sheets-Sheet 2 W m W R NW $0 5 P f a 4/ Kuhnw AAAA/ A A/AN M QM 7 EN NM 2% \5 F I. I If Patented Dec. 14, 1943 2,336,885 FITTING CONSTRUCTION FOR, TANKS Francis J. Pepersack, Towson, Md., assignor to The Glen L. Martin Company,

Middle River,

Md., a corporation of Maryland Application July18, 1942, Serial No. 451,476

3 Claims. (Cl. 285-25) The present invention pertains to a fitting construction for tanks and, more particularly. to one for tanks adapted to contain liquid hydrocarbons and comprising a rubber-like cell within a rigid housing structure.

Tanks of this nature have been found useful as fuel and oil tanks for airplanes, in which case they are fitted into the dlfierent parts of an aircraft fuselage or wing so that the normal structure provides the rigid confining element of the tank. For an example of this practice, reference may be had to Gray et al. Patent No. 2,102,590 disclosing a cellular form of tank applied to aircraft construction.

It is to be distinctly understood that the cellular form of tank under consideration is likewise adaptable to all kinds of transport vehicles and especially to ships and barges.

In a co-pending application Serial No. 423,646, filed December 19, 1941, now Patent No. 2,321,417, granted June 8, 1943, in the name of the present inventor, there is disclosed and claimed broadly a tank construction involving a cell of rubber-like material subject to cold flow under pressure and provided with a rigid ring about a fitting opening adapted to prevent pressure and deleterious cold flow when clamped to the rigid housing structure by an appropriate fitting. This previously filed application also contains disclosure and claims to certain forms of tank fittings adapted for use with a cellular tank provided with a rigid ring and, also, to cellular tanks not employing this feature. The invention to be disclosed in detail herein represents specific improvements in the manner of attaching a tank fitting to a rigid housing structure and to a cellular tank reinforced about its opening with the non-resilient ring characterizing the earlier application. Specifically novel forms of special fittings for use with cellular tanks will also be disclosed and claimed.

One ofthe principal objects of this invention is to provide a rigid ring about the fitting opening in a rubber-like tank cell with a plurality of openings for receiving threaded members so that a clamping flange member may be secured on.

the inner side of the cell about its opening independently and outwardly of the tank fitting which extends into this opening. For convenience in assembly, it is also intended to provide an arrangement of the threaded attaching members such that some may be employed for attaching the flange member to the tank cell only while others will perform ahanging function by securing the flange member to the rigid housing structure as well as the tank cell.

An additional object of the invention resides in the provision of a clamping flange member, such as previously indicated, with a portion extending outwardly into or through the tank opening for supporting the fitting or device so that the latter may be attached to this flange portion by screws or the like inserted from without the tank construction.

It is a specific object of the invention to provide eflicient means for mounting fittings or de-' vices such as liquid level gages, fillers and tank outlets, to a tank construction which porated in an aircraft.

Other features of novelty contributing to the simplicity of the tank construction, the attachment of the fittings or devices and the emciency of such fittings or devices in use will be pointed out in connection with the following detailed description of several illustrative embodiments of the invention taken in connection with the accompanying drawings, in which Fig. 1 is a fragmentary view partly in vertical section of a tank construction having a fitting in the form of aliquid level meter mounted thereon;

Fig. 2 is a similar view showing a variation of the liquid meter fitting and the tank cell to which it is connected;

Fig. 3 is a side elevation partially sectioned illustrating a front outlet fitting applied to the form of cellular tank represented by Fig. 1;

Fig. 4 is a fragmentary vertical section showing an attaching detail of Fig. 3;

Fig. 5 is a vertical section illustrating a different form of tankfiller connected in a special manner to the type of rigid structure and tank cell shown in Fig. 1.

Referring to Fig. 1, a standard form of meter or liquid level gage I0 is shown in association with a tank cell 12 enclosed by a rigid housing structure indicated generally as M.

-The tank cell 12 is of the self-sealing variety and includes an inner sealant layer l6, an inis incortration. The outer layer 28 which is adjacent the housing structure I4 is by preference formed of soft vulcanized rubber. These three layers which are adhesively bonded after suitable surface treatment comprise thesubiect-matter of or tubing 22 closely fitted within a cell opening 24 defined by the cell layers I8, I8 and 28, and having the total thickness of these layers in unstressed condition. The non-resilient or rigid ring 22 is preferably formed from a phenolic condensate material such as Bakelite, or from molded fiber, and has the important function of preventing cold flow of the cell layers about the opening. The tank cell I2 also includes an inner reinforcing fining 26 of a material which is unaffected by liquid hydrocarbon fuels, adhesively bonded in place and overlapping the underside of the ring 22. An inner reinforcing member 28 of washer shape and a somewhat thinner seam cover 28 also underlie the ring 22 and extend about the cell opening. The lining, reinforcing members and seam cover will be of fabric impregnated with a rubber-like composition. An outer reinforcing member 38 surrounds the cell opening, covers the ring 22. and overlaps the outer surface of the tank cell I2. It will be further understood that the various fabric layers reinforcing the cell opening are adhesively secured to each other or the tank cell I2.

The device I8 has an attaching flange 32 extending around its bottom and resting upon a tubular or upper flange portion 34 of a,v shouldered metallic ring 38, the joint being sealed by a conventional gasket 38. A circumferentially spaced series of screws 48 extend through the attaching flange 32 each into a respective tapped boss 42 forming a part of the tubular flange portion 34 which extends through the opening of the tank cell I2. Washers 44 are employed beneath the heads of the screws 48.

It will beobserved that the shouldered ring 36 includes an inwardly disposed flange member 46 approximately co-extensive in width with'the rigid ring 22 which it underlies and being provided with ridges 48 for clamping the tank cell I2. At suitable spacing the flange member 46 is provided with bosses, such as the drilled one 58, for receiving threaded means-in the form of a bolt or screw 52 passing downwardly through the ring 22 and having its head 54 countersunk therein. A washer 56 and a stop nut 58 on the inner end of the bolt 52 secure the tank cell I2 to the flange member 46 independently of the housing structure I4. By such means, the tank cell I2 and internal flange member 46 may first be secured together prior to attachment of the device I8.

At other circumferential points blind tapped bosses, such as 68, will be formed beneath the flange member 46 for receiving individual screws 62 each having a washer G4 beneath its head and extending through the rigid housing structure I4 as well as the rigid ring 22 of the tank cell and into threaded engagement with the flange member 48 for securing all of these parts together and the level gage or device I8 thereto.

The embodiment of the invention shown in Fig. 2 is quite similar to the one previously described in that it includes a liquid meter I8 Joined to the housing structure I4 and a tank cell I2, the lattertbeing modified in some particulars now to be noted.

In this instance, the pliant tank cell 12 is composed of a relatively thin wall layer 14 of synthetic rubber, such as neoprene or any material which is unaffected by liquid hydrocarbon fuels, and reinforced about the vent opening by an inner reinforcement layer I6 resembling a large washer and preferably formed from a heavy fabric impregnated with neoprene or equivalent hydrocarbon resstant material. As in the cell construction of Fig. 1, this reinforcement member I6 has its seam covered and inner surface sealed by a layer I8, preferably of balloon cloth fabric impregnated with neoprene or the like and adhesively attached. An outer reinforcing member 88 similar-in all respects to the inner member 16 but of somewhat larger outside diameter is adhesively secured to the cell wall 14 and completes the reinforcement of its opening.

In view of the substantial identity of the fitting in this embodiment, only brief referencewill be made to its essential details. The liquid meter I8 is provided with a circular attaching flange 82 through which pass a circumferentially spaced series of attaching screws 84 threaded into underlying tapped bosses 86 at the outer or upper end of a shouldered and flanged ring 88 extending through the housing structure I4 and the tank cell I4. As in the embodiment which has been described, the tubular portion of the ring 88 is terminated by an outwardly extending flange 98, ridged at 92 and underlying the surface surrounding the opening of the tank cell 12.

Clamping engagement between the rigid housing structure I4, the reinforcing portion of the tank cell I2 and the flange 88 of ring 88 is accomplished by means of an additional circumferentially spacedseries of inwardly extending screws 94 threadedly engaging corresponding blind tapped bosses 96 after passing through the rigid structure I4 and the tank cell I2.

For purposes of assembly, the shouldered ring 88 may be extended outwardly through the opening of the tank cell I2 and secured thereto by means of the screws 84 engaging its inner flange 98 prior to attachment of the flange 82 of the meter or device I8 to the upper end or flan e of the ring 88.

In Fig. 3, a front outlet fitting I88 for the tank cell I2 illustrates a further application of the principles of this invention to the self-sealing, multiple layer type of cell.

In the manner previously described, a nonresilient ring I82 of tubular shape and having ridges I84 on its-upper surface is inserted snugly within the opening of the tank cell I2 and has the total thickness of the layers of that cell in unstressedcondition. A circular flange I86 on the outlet fitting or device I88, is sealed by a circular gasket I88 interposed between it and the inner layer of the rigid housing structure I4 with which it is in face-to-face relation. A

' tubular member H8 forming a continuation of curing means for clamping the ring I02 and its attached tank cell I2 to the tubular member IIO. Two other sets of attaching screws H8 and I20 are employed in assembling and securing the various parts of the fitting and tank together. The screws or threaded members I20, of which one is shown on the right side of Fig. 3, engage blind tapped bosses I22 and have their heads countersunk, as shown, in the inner layer I24 of the rigid housing I4, thus serving as a hangar supporting the tank cell I2 and attached tubular member IIO within the housing structure I4 before the outlet fitting or device I is in place.

At the left of Fig. 3 it will be observed that the heads I26 of the largest threaded members H8 are tightened down upon the upper face of the flange I06 by reason of threaded engage- I ment between the screws H8 and blind tapped bosses I28 formed on the tubular member H0. The heads I26 of the screws II8 have a wire I30 laced therethrough and extending between all of the heads so that none of the screws can come loose. When the screws II8 are in place, the ring portion of the tank cell I2 will be securely clamped between the flanges I06 and H2.

While Fig. shows another form of tank filler designated generally as I10, applied to the multiple layer form of tank cell I2, this modificationv of the invention includes also special features which will now be described. The filling device I10 comprises a cylindrical screen I12 within the inside of tank cell I2 and in alignment with its opening, which screen is supported by an outwardly extending attaching flange I14 overlying the rigid housing structure I4 about the tank opening, and having sealing gaskets I16 and I18 on its respective faces. The gasket I18 is co-extenslve with and underlies a rigid spacer ring I80 having its inner periphery aligned with that of the non-resilient ring defining the opening in tank cell I2. Both rings will preferably be formed of a phenolic condensation product. on its upper side the spacer ring 180 supports another attaching flange I82 forming with flange I 14 a spaced parallel pair.

The underface of flange I82 is sealed by a gasket I84 andthe upper face of I82 is covered by a circular sealing patch I86 of neoprene or equivalent material sealed to a spaced portion of the housing structure I4, as shown. A metallic ring I88 is suitably drilled at spaced points to receive a series of bolts I90 having their heads counter sunk therein and extending through both nonresilient rings, the intervening flanges I14 and I82 and an inner ridged flange-member I92. Stop nuts I 94 engage the inner flange member I92 and retain this assembly in its clamped relation.

For preliminary mounting purposes, an intermediate spaced series of bolts I96 are passed through the inner part of the rigid housing I4 and through the tank cell and the inner flange member I92 so as to support the tank cell I2 on the housing structure while the fitting I10 is being attached thereto by means of the bolts I90.

The foregoing detailed description of several referred embodiments of the invention serves to demonstrate its advantages in attaching various forms of fitting devices to cellular tanks and their rigid confining structures when the tank opening must be free from restrictionby the attaching means.

The term ring" as used in the specification and the appended claims with respect to the member defining the tank cell opening or the spacer member of Fig. 5 is intended to mean any form of continuous or annulus member of round, rectangular, or other shape such as may be dictated by the dimensions of the space available and the nature of the device to be attached.

It will be apparent from the embodiments of the invention which have been described that changes may be made in the details of construction and arrangement of parts without departing from the spirit of the invention and the scope of the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A fitting construction for liquid fuel or lubricant tanks comprising a tank cell formed of one or more layers of rubber-like material subject to cold flow and having an opening through the wall thereof; a ring of non-resilient material having the total thickness of the cell material in uncompressed condition and fitted within the opening of said cell and having a plurality of holes formed therein; sealing layers secured to the inner and'outer sides of the tank cell about its opening and arranged to cover the abutment lines between said ring and said cell; a rigid structure confining said tank cell and provided with an opening in alignment with that of the tank cell; a flange member underlying the non-resilient ring on the inside of the tank cell; and a plurality of threaded fasteners extending through the rigid structure and through said holes in the non-resilient ring to engage the flange member to secure said flange member to the tank cell and the rigid structure.

2. A fitting construction for liquid fuel or lubricant tanks comprising a tank cell formed of one or more layers of rubber-like material subject to cold flow and having an opening through the wall thereof; a ring of non-resilient material having the total thickness of the cell material in uncompressed condition and fitted within the opening of said cell and having a plurality of holes formed therein; sealing layers secured to the inner and outer sides of the tank cell about its opening and arranged to cover the abutment lines between said ring and said cell; a rigid structure confining said tank cell and provided with an opening in alignment with that of the tank cell; a flange member underlying the non-resilient ring on the inside of the tank cell,

said flange member having a tubular portion extending outwardly into the opening of the tank cell; a device having an attaching flange engaging said tubular portion; a plurality of threaded fasteners extending through the rigid structure and through the non-resilient ring and engaging the flange member tosecure said flange member to the tank cell and the rigid structure; and screws securing the attaching flange of the device to said tubular portion.

3. A fitting construction for liquid fuel or lubricant tanks comprising a tank cell formed of one ormore layers of rubber-like material subject to cold flow and having an opening through the. wall thereof; a ring of non-resilient material having the'total thickness of the cell material in uncompressed condition and fitted within the opening of said cell and having a plurality of holes formed therein; sealing layers secured to the inner and outer sides of the tank cell about its opening and arranged to cover the abutment lines between said ring and said cell; a rigid structure confining said tank cell and structure; and a device having an attaching flange extending in face-to-face relation with the rigid structure about its opening; and additional threaded means extending through the attaching flange, the rigid'structure, the n0n-resilient ring, and into the flange member.

FRANCIS J. PEPERSACK. 

